So I installed Ubuntu 12.04 and I have no HUD. I was able to bring up Firefox only from my settings menu by clicking on a link for more information on cloud. Where is my HUD? I have no access to my programs at all?
If the HUD is not working, then you should select Ubuntu 2D at the login screen to avoid the issue for now and give you a working desktop. Then, if there is an underlying problem, it will be easier to find and to fix.